Hinge for connecting a hood, especially an engine hood, to a vehicle body

ABSTRACT

A hinge for connecting a hood, especially an engine hood, to a vehicle body, having a least one hinge carrier arranged on the vehicle body, at least one hinge arm arranged on the hood and at least one connecting part for the pivotable connection of the hinge arm to the hinge carrier. The connection of the hinge arm to the hinge carrier is released in the event of an accident by removal and/or destruction of the connecting part. The connecting part is configured to be removed and/or destroyed by forces acting in a direction of a pivot axis of the hinge, in the event of an accident.

DESCRIPTION

The invention relates to a hinge for connecting a hood, especially anengine hood, to a vehicle body in accordance with the precharacterizingclause of claim 1, and to an airbag for opening a hood connected by ahinge to a vehicle body in accordance with the precharacterizing clauseof claim 18.

Different measures have been proposed in order to protect pedestrians inthe event of accidents with motor vehicles. There are various approachesto reducing the loads to which a pedestrian's head is subjected when heimpacts against a motor vehicle. Currently known, active systems arefocused on raising the engine hood in the region of the cowl. This makesit possible, by deformation of the engine hood, for energy from thepedestrian involved in the accident to be dissipated without him cominginto contact with rigid parts situated under the engine hood. However,the engine hood is conventionally connected to the vehicle body in theregion of the cowl via a hinge.

It is therefore the object of the present invention to specify a hingewhich makes improved protection for pedestrians possible.

The object is achieved by a hinge having the features of claim 1 andhaving the features of claim 2.

Accordingly, the hinge for connecting a hood, especially an engine hood,to a vehicle body is designed in such a manner that the hood is releasedfrom the hinge in the event of an accident, especially with apedestrian.

The object is furthermore achieved by a hinge for connecting a hood,having at least one hinge carrier arranged on the vehicle body, at leastone hinge arm arranged on the hood and at least one connecting part forthe pivotable connection of the hinge arm to the hinge carrier, theconnection of the hinge arm to the hinge carrier being released in theevent of an accident by the connecting part.

In this case, the engine hood hinge can be released by completeseparation of the engine hood and vehicle body, with, in this case, adevice which limits the movement of the engine hood additionally havingto be provided. On the other hand, the release of the engine hood hingecan be brought about by only parts of the hinge connection beingreleased, so that there is not a complete separation between the enginehood and vehicle body, with the desired freedom of movement during theraising of the engine hood nevertheless being provided. In this case,the movement of the engine hood can likewise be limited by thenon-separated connection.

Claims 1 to 17 describe various options for releasing the hood,especially the engine hood, from the vehicle body. These principlesinclude, among others, the use of an explosive screw (pyrotechnically),the use of shear pins and the use of an airbag for releasing the hinge.In the case of using shear pins with an airbag being used to raise theengine hood, it is expedient to introduce the airbag forces as close tothe hinge as possible in order to enable an efficient and low-vibrationshearing off of the shear pins. The expansion of the airbag can be usedto exert tensile or shearing forces on a connecting element connectingthe two hinge parts, in particular a bolt, this bolt then beingdisengaged from at least one of the two other hinge parts by the forcesexerted.

In the case of complete separation of the engine hood in the hingeregion from the vehicle body, further measures have to be taken so thatthe engine hood, after release from the hinge, does not exhibituncontrolled behavior and could possibly be a risk to a pedestrian. Forexample, rebound straps may be used here, in which case the expansionbehavior of the rebound straps and additional rip seams placed in therebound strap may contribute to the engine hood moving as gently aspossible at a defined force level into its erected end position. Thisenables vibrations of the engine hood in association with the erectionthereof to be reduced and the period of time for damping unavoidablevibrations to be reduced.

By means of a complete or partial release of the hinge connection, amovement of the engine hood about a rotation point on the vehicle frontis possible. Inadvertent damage to the engine hood, the hinge and theadjacent vehicle regions can thus be minimized. In order to optimize therotation point of the engine hood in the front vehicle region, it may benecessary to provide additional devices which render the engine hoodpivotable in the event of an accident. In this case, the rotation pointmay be shifted, for example by means of a lever mechanism, in such amanner that the engine hood is freely pivotable in the desired regionwithout striking against remaining vehicle regions.

The invention is explained in brief below with reference to the drawingsof the figures.

FIG. 1 shows a general hinge construction, the hinge being composed of ahinge carrier 1, which is usually connected to the vehicle body, a hingearm 2, which is usually connected to the engine hood, and a connectingpart in the form of a hinge bolt 3. The hinge arm 2 is pivotable inrelation to the hinge carrier 1 about the axis of the hinge bolt 3.

FIG. 2 shows a hinge according to the invention in a state in which theseparation of the engine hood and vehicle body from the hinge hasalready been completed. The hinge bolt 3 was replaced here by anexplosive bolt, so that the connection between the hinge arm 2 and thehinge carrier 1 is separated by the explosive bolt blasting off. In thestate shown in FIG. 2, an airbag 6 situated under the engine hood, whichis connected to the hinge arm 2, has already lifted off the hinge armfrom the hinge carrier. The movement of the hinge arm 2 in relation tothe hinge carrier 1 is limited by a rebound strap 4 which is arrangedbetween the hinge carrier and hinge arm. The rebound strap firstly hasrip seams and is secondly of elastic design, so that, upon deployment ofthe airbag 6, the engine hood is transferred relatively gently into itsend state and vibrations of the engine good are therefore avoided.

FIG. 3 shows a further embodiment of the hinge according to theinvention. In this case, the hinge arm 2 is connected to the hingecarrier 1 via a shear pin 3. In the event of the deployment of theairbag (not shown here), the shear pin 3 is sheared off by the forcesexerted by the airbag, so that the connection between the hinge arm 2and the hinge carrier 1 is eliminated. The engine hood can thus betransferred into its open position.

FIG. 4 shows a further embodiment of the hinge according to theinvention. In this case, the connecting part in the form of a bolt 3 isconnected to an airbag bypass 4 via a transmission element 5. If theairbag is ignited, then the elastic airbag bypass 4 expands and, via thetransmission element 5, pulls the bolt 3 out of its original position.The hinge carrier 1 and connecting arm 2 are therefore released fromeach other.

FIG. 5 shows an embodiment of the hinge according to the invention, inwhich the airbag 6 is longer in its original state than in its inflatedstate. The airbag 6 is connected to the bolt 3 of the hinge via atransmission element 5. If the airbag 6 is inflated, its original lengthis shortened and the bolt 3 is pulled out of its connection via thetransmission element 5, as a result of which the hinge arm 2 and hingecarrier 1 are released from each other. The bolt 3 may be pretensionedhere by a spring, in the same manner as in the embodiment shown in FIG.4. When the airbag relaxes, the bolt will therefore snap back again intoits original position.

FIG. 6 shows a hinge according to the invention in the form of a balland socket hinge. The connecting part 3 is designed here in the form ofa ball which is fitted directly onto the hinge arm 2. The sphericalconnecting part 3 is accommodated in a two-part hinge carrier whichcomprises a fixed part 10 and a part 11 which can be pivoted about anaxis 12. The spherical connecting part 3 is accommodated in this case incorresponding sockets on the hinge carrier parts 10 and 11. The hingecarrier parts 10, 11 are connected to each other via a clamp 13. If aforce is exerted on the transmission element 5 by a deploying airbag 6,then the clamp 13, which is arranged on the transmission element 5, isreleased from the two hinge carrier parts 10, 11, so that the moveablehinge carrier part 11 folds about the axis 12 and releases the sphericalconnecting element 3.

FIG. 7 shows a further embodiment. In this case, the hinge arm 2 has adeformation region 20 in which the hinge arm 2 can be deformed. If anairbag arranged under the engine hood is ignited, then the deformationregion 20 of the hinge arm 2 is deformed, with the result that theconnecting part 3 migrates out of a socket 100 on the hinge carrier 1and thereby releases the connection. It migrates out owing to theshortening of the hinge arm 2 that is projected onto the socket 100. Theopening movement is controlled by a lever 4 which moves in a coulisse 40on the hinge carrier 1. As a result, a defined opening behavior can beachieved. A further possible coulisse guide, for example for theconnecting part 3, is shown in the upper region of FIG. 7. In an initialposition, the connecting part 3 is securely clamped in the region 41 ofthe coulisse guide behind a locking element 42. If an airbag isdeployed, then the part 3 migrates on the path indicated by the arrowpast a one-way flap 43 into the open position 45. After the accident,the hood can be brought by pressing down from the region 45 past theone-way flap 43 again into a transportation position 44 in which ajourney to the next workplace is possible.

FIG. 8 shows a further embodiment, in which the deployment of an airbag6 acts again, via a transition element designed as a lever 6, on thebolt 3 in such a manner that, when the airbag 6 is deployed, the bolt ispulled back out of its connection. The airbag operates here in the formof a piston and is adjacent to piston-shaped caps 62.

FIG. 9 shows a particular embodiment of a suitable airbag 6. In thiscase, the airbag is positioned in the vehicle in such a manner that itis situated in the direct vicinity of the hinges of the engine hood. Agas lance 60, the outlet openings of which are likewise arranged in thedirect vicinity of the hinges, is arranged in the airbag 6. If a gas fordeploying the airbag 6 is generated by the gas generator 61, then, asshown under I., the airbag region which is situated in the region of thehinges is inflated first of all. Only then is the remaining airbagdeployed. The effect achieved by this is that preliminary forces occurinitially in the region of the hinges, said forces enabling the hinge tobe released and only then is the rest of the engine hood raised. Thisprevents the engine hood from unnecessarily vibrating.

1. (canceled)
 2. A hinge for connecting a hood to a vehicle body, havinga least one hinge carrier arranged on the vehicle body, at least onehinge arm arranged on the hood and at least one connecting part for thepivotable connection of the hinge arm to the hinge carrier, wherein thehinge is configured so that the connection of the hinge arm to the hingecarrier is released in the event of an accident by removal and/ordestruction of the connecting part due to forces acting in a directionof a pivot axis of the hinge.
 3. The hinge as claimed in claim 2,wherein the connecting part is designed as an explosive bolt or shearbolt.
 4. The hinge as claimed in claim 2, wherein the connecting part isguided in at least one socket on the hinge arm and in at least onesocket on the hinge carrier and, in the event of an accident, is removedfrom at least one socket.
 5. The hinge as claimed in claim 4, whereinthe connecting part is designed as a bolt which is pulled out of atleast one of the sockets.
 6. The hinge as claimed in claim 4, wherein atleast one actuating device is provided for actuating the connecting partin the event of an accident.
 7. The hinge as claimed in claim 6, whereinthe actuating device comprises a pyrotechnic element.
 8. The hinge asclaimed in claim 6, wherein the actuating device is an inflatable airbagand/or a gas-conducting element.
 9. The hinge as claimed in claim 8,wherein the airbag and/or the gas-conducting element acts on theconnecting part via a least one transmission element.
 10. The hinge asclaimed in claim 9, wherein the transmission element is designed as alever.
 11. The hinge as claimed in claim 9, wherein on filling with gas,the airbag and/or the gas-conducting element, owing to its expansion,exerts a push or a pull on the connecting part and/or the transmissionelement.
 12. The hinge as claimed in claim 2, wherein the hinge carrierhas at least one socket which corresponds with the connecting part andis configured to release the connecting part in the event of anaccident.
 13. The hinge as claimed in claim 12, wherein the hingecarrier has at least one moveable hinge carrier part which, in the eventof an accident, is moved in relation to at least one fixed hinge carrierpart in such a manner that the connecting part accommodated thereincomes free.
 14. The hinge as claimed in claim 2, wherein the hinge armhas a deformation region for the specific deformation of the hinge armin the event of an accident.
 15. The hinge as claimed in claim 14,wherein the connecting part is disengaged from the hinge carrier bydeformation of the hinge arm.
 16. The hinge as claimed in claim 2wherein at least one limiting device is arranged for limiting therelative movement between the hinge carrier and hinge arm.
 17. The hingeas claimed in claim 16, wherein the limiting device is a rebound strapand/or a lever guided in a coulisse.
 18. An airbag for opening a hoodconnected by a hinge to a vehicle body, especially an engine hood,wherein the airbag is configured to release the hood from the vehiclebody when deployed in the region of the hinge.
 19. The airbag as claimedin claim 18, wherein airbag regions are arranged directly on the hinge.20. The airbag as claimed in claim 19, wherein the airbag, whendeployed, is first of all deployed in the regions arranged on the hinge.21. The airbag as claimed in claim 19, wherein a gas-conducting system,in particular a gas lance, is arranged in the interior of the airbag,said lance conducting the gas used for the deployment into the airbagregions arranged on the hinge.